__author__='CQC'
#coding:utf-8
import urllib
import urllib2
import re
#定义一个页面标签处理类
class Tool:
    #去除img,7为长空格
    removeImg = re.compile('<img.*?>| {7}|')
    #删除超链接
    removeAddr = re.compile('<a.*?>|</a>')
    #把换行标签换为\n
    replaceLine = re.compile('<tr>|<div>|</div>|</p>')
    #把表格替换为\n
    replaceTD = re.compile('td')
    #把段落开头换为\n加两空格
    replacePara = re.compile('<p.*?>')
    #将换行货双换行符替换为\n
    replaceBR =re.compile('<br><br>|<br>')
    #将换行余标签剔除
    removeExtraTag = re.compile('<.*?>')
    def replace(self,x):
        x =re.sub(self.removeImg,"",x)
        x =re.sub(self.removeAddr,"",x)
        x =re.sub(self.replaceTD,"\n",x)
        x =re.sub(self.replacePara,"\n  ",x)
        x =re.sub(self.replaceBR,"\n",x)
        x = re.sub(self.replaceLine,"\n",x)
        x = re.sub(self.removeExtraTag,"",x)
        #strip()将前后多样内容删除
        return x.strip()

#定义一个百度贴吧的类
class BDTB:
    #初始，传入地址
    def  __init__(self,baseUrl,seeLZ,floorTag):
        #base链接地址
        self.baseURL = baseUrl
        #是否只看楼主
        self.seeLZ = '?see_lz='+str(seeLZ)
        #html标签剔除工具类对象
        self.tool= Tool()
        #全局file变量
        self.file =None
        #楼层标号，初始为1
        self.floor =1
        #默认标题，如果没有成功获取标题的话则会用这个标题
        self.defaultTitle = u'百度贴吧'
        #是否写入楼分隔符标记
        self.floorTag = floorTag

    #传入页码，获取该页帖子的代码
    def getPage(self,pageNum):
        try:
            url =self.baseURL+self.seeLZ+'&pn='+str(pageNum)
            request = urllib2.Request(url)
            response =urllib2.urlopen(request)

            return response.read().decode('utf-8')
        except urllib2.URLError, e:
            if hasattr(e,'reason'):
                print u'连接贴吧失败，错误原因：',e.reason
                return None
    #获取帖子标题
    def getTitle(self,page):
        #得到标题的正则
        pattern =re.compile('<h3.*?>(.*?)</h3>',re.S)
        result =re.search(pattern,page)
        if result:
            #如果存在，则返回标题
            return result.group(1).strip()
        else:
            return None
    #获取贴子一个有多少页
    def getPageNum(self,page):
        #获取帖子页数的正则
        pattern = re.compile('li class ="l_pager pager_theme_.*?<span class="tP">(.*?)</span>',re.S)

        result = re.search(pattern,page)
        if result:
            return result.group(1).strip()
        else:
            return None

    #获取每一层楼的内容，传入页面内容
    def getContent(self,page):
        #匹配所以楼层的内容
        pattern =re.compile('<div class="p_content>(.*?)<div class="d_author">',re.S)
        items =re.findall(pattern,page)
        contents = []
        for item in items:
            #将文本进行去除标签处理，同事在前后加入换行腐恶
            content="\n"+self.tool.replace(item)+"\n"
            contents.append(content.encode('utf-8'))
        return contents

    def setFileTitle(self,title):
        #如果标题不是为None,既成功获取标题
        if title is not None:
            self.file =open(title + ".txt","w+")
        else:
            self.file =open(self.defaultTitle+'.txt',"w+")

    def writeData(self,contents):
        #向文件写入每一楼的信息
        for item in contents:
            if self.floorTag =='1':
                #楼之间的分割符
                floorLine= "\n"+str(self.floor)+u"-----------------------------------------------------------------------------------------\n"

                self.file.write(floorLine)
            self.file.write(item)
            self.floor +=1

    def start(self):
        indexPage =self.getPage(1)
        pageNum = self.getPageNum(indexPage)
        title =self.getTitle(indexPage)
        self.setFileTitle(title)
        if pageNum ==None:
            print "URL已失效，请重试1"
            return
        try:
            print "该帖子共有"+str(pageNum)+"页"
            for i in range(1,int(pageNum)+1):
                print "正在写入第"+str(i)+"页数据"
                page =self.getPage(i)
                contents = self.getContent(page)
                self.writeData(contents)
            #出现写入异常
        except IOError,e:
            print "写入异常，原因"+e.message
        finally:
            print "写入任务完成"

print u"请输入帖子代号"
baseURL = 'https://tieba.baidu.com/p/'+str(raw_input(u'链接'))
seeLZ =raw_input("是否 只获取楼主发言，是输入1，否输入0")
floorTag = raw_input("是写入楼层信息，是输入1，否输入0|n")
bdtb = BDTB(baseURL,seeLZ,floorTag)
bdtb.start()

